What it's made of makes all the difference. ROCKWOOL insulation is created from a unique combination of stone and recycled slag. The ROCKWOOL Group is the world’s leading manufacturer of stone wool insulation. We offer a full range of high-performing and sustainable insulation products for the construction industry. ROCKWOOL insulation products have outstanding fire, acoustic and thermal insulation properties, as well as highly-recognized sustainability credentials. Those traits have led to our products to being installed in commercial and residential buildings of all types.